Happy Holy Theophany to everyone! This's my first note in English in here. Please, correct me.

Hello!

- This is.  We never shorten "is" to " 's" after an "s" sound (or a "z" or a "sh").  So, "this is" is always written in full (even though when we speak, if we are speaking quickly, we may make it sound shorter.) 

- Also, we don't need a comma (",") after "please."  When we speak, there is no pause there.  So "Please correct me." 

Hope this helps!